Klotho upregulation contributes to the neuroprotection of ligustilide in an Alzheimer's disease mouse model

Klotho, an aging-suppressor gene, encodes a protein that potentially acts as a neuroprotective factor by modulating insulin-like growth factor 1 signaling and oxidative stress. In the present study, we investigated the potential role of Klotho in the therapeutic effect of ligustilide against Alzheimer’s disease (AD)-like neuropathologies and memory impairment in aged senescence-accelerated mouse prone-8 (SAMP8) mice. Ligustilide treatment (10 and 40 mg/kg for 8 weeks, intragastrically) in 10-month-old SAMP8 mice reduced memory deficits, amyloid-β_1–42 accumulation, tau phosphorylation, and neuron loss, increased mitochondrial manganese-superoxide dismutase and catalase expression and activity, and decreased malondialdehyde, protein carbonyl, and 8-hydroxydesoxyguanosine levels in the brain. Ligustilide upregulated Klotho expression in the cerebral choroid plexus and serum, decreased Akt and Forkhead box class O1 phosphorylation. Moreover, ligustilide inhibited the insulin-like growth factor 1 pathway and induced Forkhead box class O1 activation in 293T cells along with Klotho upregulation. An inverse correlation was found between Klotho expression and the AD phenotype, suggesting that Klotho might be a novel therapeutic target for age-related AD, and Klotho upregulation might contribute to the neuroprotective effect of ligustilide against AD.     

Fibroblast growth factor 23 and 25(OH)D levels are related to abdominal obesity and cardiovascular risk in patients with polycystic ovarian syndrome

Abstract

Fibroblast growth factor 23 (FGF23) and Klotho are extensively studied in relation to bone metabolism and progression of chronic kidney disease. There is very limited information about their role in polycystic ovarian syndrome (PCOS). The aim of the present study was to investigate some bone markers in women with PCOS in relation to obesity and cardiovascular risk. In the study were included 80 patients, divided into three age-matched groups –Non-obese PCOS (n?=?40); Obese PCOS (n?=?20) and Obese control group (n?=?20). Bone marker levels were measured by an enzyme-linked immunosorbent assay. Obese PCOS patients had higher levels of FGF23 and sRANKL, lower levels of 25(OH)D and higher prevalence of vitamin D deficiency compared to non-obese subjects. Patients with abdominal obesity (waist circumference >80?cm) independently of PCOS status had significantly higher levels of FGF23 (112.5?±?86.5 vs. 73.4?±?37.9?pg/ml; p?=?.023) and lower of 25(OH)D (35.8?±?21.4 vs 47.8?±?26.5?nmol/l; p?=?.034). Patients with PCOS at risk of cardiovascular diseases according to AE-PCOS consensus also had increased levels of FGF23 (111.6?±?84.5 vs. 66.5?±?35.1?pg/ml; p?=?.031) and decreased levels of 25(OH)D (31.9?±?16.8 vs. 47.1 vs 28.4?nmol/l; p?=?.017) compared to those not at risk. There was no correlation between bone markers and blood glucose levels, insulin resistance or hormonal levels.     

FGF23/Klotho在急性肾损伤中的研究进展

急性肾损伤（AKI）在世界范围内具有较高的发病率和病死率,且是慢性肾脏病（CKD）和进展为终末期肾脏病的危险因素,给患者带来日益沉重的健康负担。成纤维生长因子23（FGF23）和a-Klotho（以下称“Klotho”）通路是近年来的研究热点。AKI发生后,血清中FGF23水平迅速上升,Klotho表达下降。这两种指标...     

小鼠全长膜型Klotho蛋白cDNA表达体系的构建与应用

目的克隆编码小鼠膜型Klotho(mKL)蛋白的cDNA片段,构建、包装Klotho重组腺相关病毒表达体系,并检测rAAV/mKL载体表达功能。方法选择RT-PCR扩增小鼠全长mKL蛋白的基因片段,将该片段亚克隆至腺相关病毒载体pAAV-IRES-hnGFP,采用酶切及DNA测序鉴定;利用AAV-293细胞包装rAAV/mKL,经转染7901细胞,检测其Klotho表达情况。结果本文成功克隆出序列信息和读码框完全正确的3 064 bp的小鼠Klotho基因片段,并构建pAAV/mKL克隆。在AAV-293细胞中包装出rAAV/mKL,病毒原液转染7901细胞后其Klotho mRNA表达上调,而细胞上清液Klotho蛋白也明显增加(P<0.01)。结论成功构建小鼠Klotho重组腺相关病毒载体(pAAV/mKL),获得了rAAV/mKL,并经转染7901细胞验证其基因表达功能正常,这就为进一步研究Klotho基因治疗衰老相关性疾病提供了技术基础。     

成纤维细胞生长因子-23的代谢调控及与疾病的关系

成纤维细胞生长因子-23(FGF-23)是一种重要的骨源性调磷激素,其主要受体为成纤维细胞生长因子受体(FGFR)/Klotho复合物.多种因素共同参与FGF-23的生理及病理性调控.FGF-23的主要生理作用为调节磷和维生素D代谢.FGF-23的代谢耦联失衡可导致多种磷代谢异常疾病,如X连锁遗传性低血磷性佝偻病、常染色体显性遗传性低血磷性佝偻病、常染色体隐性遗传性低血磷性佝偻病和肿瘤性骨软化症等.随着研究的深入,已明确高水平的FGF-23在慢性肾脏疾病和心血管疾病中发挥重要的病理作用,其精确的调控网络及分子机制仍有待阐明.此外,新近的研究已初步探讨了FGF-23在糖、脂代谢中的作用.     

Effects of a Topical Anti-aging Formulation on Skin Aging Biomarkers

ObjectiveFollowing previous clinical trials, an antiaging product (Restorative Skin complex [RSC]; Alastin Skin Care Carlsbad, a Galderma company), was investigated for its effects on Klotho gene regulation, telomere length, and histological biopsy changes to provide a comprehensive picture of the mechanism and efficacy of its anti-aging effect.MethodsNeonatal human fibroblasts were used for telomere length studies to examine the effect of the full RSC formulation and the amino acid components Tripeptide-1 and Hexapeptide-12 (TriHex™) on these cellular aging mechanisms. In addition, RNA sequencing was conducted using human keratinocytes specifically investigating Klotho and related genes. This was supplemented by a clinical study using biopsy samples.ResultsTriHex™ significantly upregulated the Klotho gene and related FGF23, FGFR1 and FOXO3B anti-aging genes. Significant telomere shortening reduction over control was demonstrated with the RSC formulation at four weeks and with TriHex™ at six weeks for all percentiles tested. Previous clinical studies demonstrated that the use of the antiaging regimen for 12 weeks produced a statistically significant improvement in scores for all evaluated parameters. Restaining of previous biopsy blocks from the clinical trial revealed positive ECM changes, stimulation of collagen, fibrillin, CD44 and elastin.LimitationsThe study was limited by a relatively small numbers of patients in the clinical trial and the non-competitive nature of the trial.ConclusionRSC anti-aging formulation and its TriHex™ components demonstrated significant reduction in telomere shortening, upregulation of Klotho and FOXO3 genes and biopsy validation of anti-aging efficacy. This new science supplements previous trials that demonstrated clinical efficacy of the formulation.     

Defect in parathyroid-hormone-induced luminal calcium absorption in connecting tubules of Klotho mice.

BACKGROUND: Homozygous Klotho mutant mice (KL(-/-) mice) exhibit multiple phenotypes resembling human ageing. Increases in the ratio of urinary calcium to urinary creatinine (uCa/uCr) and in serum Ca concentration and decreases in urinary Cr excretion and serum parathyroid hormone (PTH) concentration were reported; however, precise information about renal Ca handling was not reported in these animals. METHODS: We evaluated the PTH-induced increase in intracellular Ca(2+) concentration ([Ca(2+)]i) in cells of isolated perfused connecting tubules (CNTs) of KL(-/-) mice. We also determined fractional excretion of Ca from the urine and serum samples of the same animals (n = 7), and compared them with KL(+/+) mice and hemi-nephrectomized KL(-+/+) mice (n = 10 in each) as controls. RESULTS: FECa was significantly higher in KL(-/-) mice than in controls (0.67 +/- 0.13 vs 0.20 +/- 0.04%). The PTH (10 nM)-induced increase in [Ca(2+)]i was diminished in KL(-/-) mice (58 +/- 5 vs 231 +/- 15 nM). Addition of 10 nM of 8-(4-chlorophenylthio)-cyclic adenosine 3',5'-monophosphate had a similar effect. The PTH-induced increase had completely disappeared by the removal of Ca from lumen and bath in both groups of animals. Removal of sodium (Na) from the solution increased [Ca(2+)]i to a similar extent in both groups. Conclusion. We conclude that renal Ca excretion estimated by determining FECa was defective in the KL(-/-) mice. Impairment of Ca absorption from the lumen by stimulation of PTH in CNTs is one of the mechanisms of this defect. Activity of the basolateral Na/Ca exchanger was preserved in this strain. Therefore, the pathway downstream after generation of second messengers following stimulation of PTH (such as the sorting of transporters of Ca absorption) might be impaired by disruption of the Klotho gene.     

冬虫夏草对自发性高血压大鼠肾脏Klotho表达和肾小管上皮细胞凋亡的影响

目的 观察自发性高血压大鼠（SHR）肾脏Klotho表达和肾小管上皮细胞的凋亡情况以及冬虫夏草对其的影响,探讨冬虫夏草在高血压肾损伤肾小管上皮细胞凋亡中的保护作用机制。 方法 按随机数字表法将20只22周龄雄性SHR分为模型组（SHR）、冬虫夏草组、氯沙坦组、冬虫夏草＋氯沙坦组,以5只22周龄雄性Wistar-Kyoto（WKY）大鼠为对照组。测定尿蛋白量（24 h）、NAG、Scr、BUN水平,并观察肾脏病理改变;RT-PCR法观察肾组织Klotho、p53和p21 mRNA表达;Western印迹法检测肾组织Klotho、p53、p21和活性caspase-3蛋白表达;原位缺口末端标记法（TUNEL）检测肾小管上皮细胞凋亡。 结果 与SHR组相比,冬虫夏草组、氯沙坦组、冬虫夏草＋氯沙坦组尿蛋白量（24 h）[（52.16±29.3） mg、（49.97±32.5） mg、（54.67±30.09） mg比（96.52±36.94） mg]、尿NAG[(44.13±9.11)、(42.75±8.33)、（41.96±7.88） U/L比（54.07±6.57） U/L]、Scr[（45.25±9.55）、（43.76±8.65）、（45.18±7.28） μmol/L比（53.84±10.21） μmol/L]和BUN[（8.25±1.03）、（8.40±1.58）、（8.32±0.98） mmol/L比（8.91±1.24） mmol/L]均显著减少（均P ＜ 0.05）,肾脏病理损害减轻,同时肾脏Klotho表达显著上调（P ＜ 0.01）,而p53、p21及活性caspase-3表达均显著下调（均P ＜ 0.01）,肾小管上皮细胞凋亡显著减少（分别为7.56%±0.52％、7.93%±0.37％、7.37%±0.36％比13.32%±0.64％,均P ＜ 0.01）,各药物干预组间差异无统计学意义（P ＞ 0.05）。 结论 冬虫夏草可能通过上调Klotho表达,抑制p53、p21的表达和caspase-3的活化,减少肾小管上皮细胞凋亡,从而对高血压肾损伤起一定的保护作用。     

不同水平高血压患者血清Klotho蛋白、NO、ET-1的表达水平及相关性

目的探讨Klotho蛋白、一氧化氮(NO)、内皮素(ET)-1在高血压发生发展中的作用及相关性。方法收集在该院住院患者96例及体检中心体检的健康对照者30例,按血压水平不同分为对照组(30例),高血压1级组(31例),高血压2级组(33例),高血压3级组(32例)。用酶联免疫吸附法(ELISA)检测血清Klotho蛋白、ET-1水平,用硝酸还原酶法测NO水平。应用生化自动分析仪检测空腹血糖、甘油三酯(TG)、总胆固醇(TC)、低密度脂蛋白胆固醇(LDL-C)、高密度脂蛋白胆固醇(HDL-C)水平。结果随血压水平升高,血清Klotho蛋白及NO水平逐渐降低,且均与血压水平存在负相关性。血清Klotho蛋白在高血压1级组与对照组相比无显著性差异(P0.05),余组间比较均有显著性差异(P0.05);血清NO水平在任意两组间均有显著性差异(P0.05)。ET-1水平随着血压水平升高而升高,与血压水平存在正相关性,高血压2级组、3级组明显高于对照组(P0.05),高血压3级组高于高血压1级组(P0.05)。Klotho蛋白与NO之间呈正相关,与ET-1之间无相关性,NO与ET-1之间呈负相关。Klotho蛋白与TC、LDL-C水平呈负相关,与空腹血糖、TG、HDLC之间不存在相关性。结论内源性Klotho蛋白分泌不足可能是高血压发生原因之一;血清Klotho蛋白、NO、ET-1水平与血压水平有明显相关性,可能共同参与高血压的发生、发展。